There are many advantages to designing a building using economically and environmentally sustainable methods. Although “green” construction materials and technologies cost more in the short term, in the long run green strategies have been shown to save money. By “going green,” the owners of the building will enjoy lower utility bills and higher resale values later on. More efficient heating and cooling will not only save on costs but will be less taxing on the environment. The key to effective green building has to do with the performance and cost trade-offs associated with the different design methods. As an example, high performance windows and window frames will at first increase the cost of the building, but the resulting increase in heating and cooling efficiency will lead to reductions in maintenance costs over time (Kats, 2010).
Green buildings can range in efficiency from “not as bad” as conventional buildings to “much better” than conventional buildings. The impact on the environment of green buildings is obviously less than that of their traditional counterparts (US Environmental Protection Agency, 2009). Ideally, a green building is one that preserves and sustains the habitat of the site as it was before it was developed.
New and green technologies are continuously being developed to either complement or replace current building practices. The main goal in developing green construction strategies is that these buildings will reduce the impact of the built environment on the health of the environment and on human health. This can be accomplished in several ways. The first and most significant strategy is to more efficiently use water, energy, and other resources (Kats, 2010). Most of the cost reductions from green construction are associated with efficient resource usage. The second strategy is to reduce waste, environmental degradation, and pollution. Finally, the impact on the environment can be minimized by protecting occupant health and safety.
Buildings that are resource-efficient throughout their life-cycle, from design to construction, operation, maintenance, and demolition, are considered to be environmentally responsible. They are also said to be sustainable (Boué, 2013). Sustainability is defined in terms of meeting the demands of present needs without compromising the ability for others to meet their needs in the future. Sustainable and environmentally responsible construction techniques often emphasize the importance of renewable resources. Renewable resources are those that can be replenished to counteract usage and consumption, usually through naturally occurring processes. Trees are an example of a renewable resource, since they can be grown and regrown, while fossil fuels, which are finitely available, are non-renewable. Renewable resources are a part of earth's natural environment and can be replenished at a rate that is comparable to or greater than the rate at which they are consumed.
There are a number of different renewable resources that can be employed in the construction of green buildings. These technologies are constantly evolving and gaining in efficiency. One method that has been growing in popularity and cost-effectiveness over the past several decades is the use of solar and photovoltaic equipment as a source of energy (Boué, 2013). In solar technology, there are what are known as passive and active building designs. In a passive solar building design, the windows, walls, and floors are constructed with photovoltaic elements to collect and store solar energy in the form of heat in the winter. In the summer, the stored energy can be used to reject solar heat, thereby cooling the building. Unlike active solar design systems, there are no mechanical or electrical devices involved in passive solar building designs. An active solar design would, for example, involve the use of solar panels to transfer heat directly to the interior space of a building.
Another sustainable construction method that makes use of renewable resources reduces water run-off by using plants and trees through green roofs and rain gardens. A green roof, also known as a living roof, is a roof that is covered with a layer of vegetation (either partially or completely). The vegetative layer sits on top of a growing medium such as soil (Kats, 2010). The entire system is planted over a waterproofing membrane so water does not leak through to the interior of the building. Green roofs have been implemented in the traditional architecture of some societies, and can be seen in the sod roofs of Sweden and the Faroe Islands. In addition to being environmentally friendly, they serve several purposes for a building. Green roofs are useful for absorbing rainwater and act as a habitat for wildlife. They provide insulation, as well as a more aesthetically pleasing building-scape. They also help lower surrounding air temperatures, as the vegetation absorbs heat, whereas tarred or tiled roofs tend to increase temperatures by reflecting heat back into the atmosphere. A report presented at the Green Roofs for Healthy Cities Conference in 2004 determined that green roofs reduce water runoff by over 75 percent and even slow the rate of runoff from the roof. They also are effective filters of carbon dioxide and pollutants from air, as well as of heavy metals from rainwater. Green roofs not only mitigate the environmental impact of construction, but can also increase the real estate value of an average building by about 7 percent. These are only a handful of the benefits that are associated with green roofs, and more are being discovered every day.
Some of the implementations of sustainable and environmentally responsible technology are small and easily retrofitted into an existing building, but can have significant benefits over time. For example, it is relatively easy to replace conventional windows with high-performance windows, such as the kind that come with low-emissivity (low-E) glazings to help with heat loss (Kats, 2010). The result is substantial savings on heating and cooling over the lifetime of the building. Water-saving appliances are another example. Water-saving dishwashers, front-loading washing machines, and toilets can save households and buildings thousands of gallons of water a year, even without changes to the occupants' water usage patterns.
Green building optimization is a many step process. The end goal is always to design a building that harmonizes with the natural landscape that surrounds it and which ideally can generate its own renewable energy on-site. A green building will also be constructed from materials taken from local sources and integrates materials efficiency into its design. In addressing the range of impacts associated with a building's design, it is often useful to use a life-cycle assessment. A life-cycle assessment (LCA) can help determine the costs and benefits of a building from the beginning to end stages of its construction. The impacts taken into account in an LCA include embodied energy, global warming potential, pollution (water and air), waste generation, and resource use. LCA is widely regarded as the best way to study the environmental responsibility and impact of a building (“Defining Life Cycle Assesment (LCA),” 2010). LCA can help builders and owners evaluate the and interpret the potential impacts of the building by contributing to the creation of an inventory of energy inputs and releases.
There are already numerous environmentally friendly building materials available to those who are interested in sustainable construction. According to the Steel Recycling Institute, the framing process of creating a building can be simplified and made more cost-effective by using recycled, customized steel beams and panels. Steel is a durable building material, and is especially effective at withstanding high winds and earthquakes. Using recycled scrap steel can help reduce the energy produced in making steel and save space in landfills.
Insulated concrete forms are another technique that buildings can implement to reduce energy costs and environmental impact. Concrete forms are defined by the Portland Cement Association as “cast-in-place concrete walls that are sandwiched between two layers of insulation material (Boué, 2013).” A study conducted by the Massachusetts Institute of Technology determined that buildings made from insulated concrete forms conserved 20 percent more energy than wood-framed buildings in cold winter climates. Alternatively, the use of gravel or permeable concrete instead of asphalt as an insulator can help with the replenishment of groundwater.
The use of straw bales for insulation is another environmentally responsible method that has been growing in popularity in recent years. According to the California Straw Building Association, straw can last for thousands of years if kept dry. Since it binds well to stucco and plaster walls, it makes a good alternative to conventional insulation materials (Boué, 2013). Straw is an agricultural byproduct that is usually disposed of through burning. By using straw in the construction of buildings instead, we avoid the release of harmful greenhouse gases into the atmosphere.
Structured Insulated Panels, or SIPs, are another way that buildings can save on energy costs while also reducing their impact on the environment. The National Association of Home Builders has determined the buildings that use SIPs save 50 percent more compared to buildings constructed from traditional materials (Boué, 2013). In addition to being more efficient, SIPs are fire resistant and can be used for foundations, load-bearing walls, ceilings, and floors.
There is no reason that Bowie State University should not design and construct buildings that are more environmentally friendly. In addition to reducing the environmental impact of the buildings, renewable resources and sustainable methods can result in reductions in the cost of heating and cooling the buildings. Existing buildings can be retrofitted with a number of low-impact technologies, such as low-emissivity windows and water-saving toilets. New buildings can be constructed from renewable materials that are both more efficient and more environmentally friendly.
1. US Environmental Protection Agency. (October 28, 2009). Green Building Basic Information. Retrieved June 26, 2015, from http://epa.gov/greenbuilding/pubs/about.htm.
2. Kats, Gregory. (September 24, 2010). Costs and Benefits of Green Buildings [Web Log Post]. Retrieved from http://thinkprogress.org/climate/2010/09/24/205805/costs-and-benefits-of-green-buildings/#
3. Boué, George. (May 7, 2013). Linking Green Buildings, Productivity and the Bottom Line [Web Log Post]. Retrieved from http://www.greenbiz.com/blog/2010/07/08/linking-green-buildings-productivity-and-bottom-line
4. United States Green Building Council. (July 27, 2012). The Business Case for Green Building Retrieved 06:08, March 9, 2014, from http://www.usgbc.org/articles/business-case-green-building
5. "Defining Life Cycle Assessment (LCA)." (17 October 2010). US Environmental Protection Agency.